Unquestionably the work of both a newbie director and a green screenwriter.

Before the first act of Wally Pfister’s directorial debut, “Transcendence,” is over, Johnny Depp’s Dr. Will Caster, a man who has become a computer, thus forming the entire narrative of the film, says without a trace of irony: “we need to get off the grid.” The man who has become a computer needs to get off the grid. Unfortunately for everyone involved – cast, audience, the theoretical population of people that exist within the world of the movie – he can’t get off the grid, because he is the grid. (Eventually, yes, Will’s wife Evelyn does try to take them off the grid, while also ignoring the fact that their change of location will only lead to a strengthening of the Will-grid.)

These kind of silly and shapeless proclamations (someone even yells “it’s Y2K!” at one point) and acts make up the majority of “Transcendence,” a relatively ambitious sci-fi outing that never lives up to its promise, no matter how many big ideas and big stars Pfister loads it up with. Depp’s Dr. Caster is a scientist concerned with understanding the world, while his wife Evelyn (Rebecca Hall) is one interested in changing it – details about their work that are delivered early on, at some sort of symposium with criminally bad security. The pair are partners both in life and in work, and they’ve spent years toiling away on a massive artificial intelligence project that threatens the ideals of a pack of cyber-terrorists who want the world to “unplug.” (One of them even has a tattoo that says as such, in case you don’t get their aims without visual cues.)

It’s one of those same terrorists who, at that poorly secured symposium, shoots Will, killing him not with his badly placed bullet, but the radiation poison it’s laced with. Distraught over his impending demise – radiation poisoning can take a few weeks – Will, Evelyn, and Max hatch a bonkers plan to use their technology to scan and “download” Will’s brain into their A.I. system. It may be a wild plan, but it’s got some pretty convenient things to push it along, like the fact that the same baddies that shot Will also blew up A.I. labs around the country (though not Will and Evelyn’s!) or that Max is a scientific genius willing to help or even that Evelyn locates an abandoned building to do their work in (not, say, their million-dollar lab). The experiment itself ultimately proves successful – Will becomes a computer! – but it comes with some scary consequences, the kind that send the Casters on the run for whole years. Will, of course, begins to evolve in rapid ways, and although his aims and ideals seem high-minded, that soon changes.

Basically – if you believe a man can be a computer, you can also believe that a computer can be a villain.

Pfister certainly throws some interesting ideas into play, many of which are imaginative on the surface and fairly obvious upon further reflection (what Will eventually “becomes” is a bit of a surprise, but it actually fits quite neatly into the trajectory of his evolution), but that level of basic cleverness is lacking throughout most of the film. Pfister also, quite bizarrely, introduces one of his most imaginative ideas – one that essentially drives the final act of the film – within the film’s opening moments. (It seems like spoiler territory to even mention it here, because it unquestionably gives away the film’s ending, and yet Pfister and screenwriter Jack Paglen put them right alongside the opening credits.) Before “Transcendence” even really boots up, we know how it’s all going to shut down, and that deflates its tension time and again.

Despite ostensibly starring Depp, the majority of his work is relegated to looking confused, then looking sick, and then existing entirely as a face on a computer screen. Instead, Rebecca Hall is the film’s true star, and she’s mostly appealing and quite believably emotional as the conflicted Evelyn. Yet while Hall is more than serviceable in her role, the film’s other leading lady doesn’t fare nearly as well. As techno terrorist Bree, Kate Mara is subjected to uneven screen time, a barely decipherable set of motivations, a shockingly bad hairstyle, and apparently very little direction, because the normally charming and compelling actress is notably off-key and uncomfortable on the screen.

The film is Pfister’s first attempt at directing – the filmmaker has long served as Christopher Nolan’s director of photography – and despite his background in film, some of the basic mechanics of solid storytelling seem to escape him. What should be simple elements are instead rendered muddy and meaningless. For one, the film has absolutely no sense of the passage of time, and large chunks of narrative flash by without any indication of how much time they’ve occupied, a slip-up made all the weirder by Pfister’s decision to occasionally throw up inter-titles that do tell us a certain amount of time has gone by. Character motivations are often shockingly unclear, and the supporting cast suffers mightily because of it. (In a particularly bad combination of the two, Paul Bettany’s Max is subjected to an imprisonment that comes with both an uncertain amount of time and a major motivation change that is never explained.)

Although “Transcendence” sure sounds like it has a pedigree – Nolan’s cinematographer! Johnny Depp! a Black List script! – the film is unquestionably the work of both a newbie director and a green screenwriter (scribe Jack Paglen has previously only written two shorts, and although the film landed on the 2012 Black List, that particular designation is not as sterling as it used to be). It’s earnest and imaginative, but it’s also unrefined and frequently just plain silly. Did it look good on paper? Let’s hope so – because it looks pretty bad on the big screen.